Non-volatile memory circuit, system, and method

Abstract

A non volatile memory device includes a first buffer register configured to receive and store the data to be stored into the memory device provided via a memory bus. A command window is activatable for interposing itself for access to a memory matrix between the first buffer element and the memory matrix. The command window includes a second buffer element that stores data stored in or to be stored into a group of memory elements. A first data transfer means executes a first transfer of the data stored in the second buffer register into the first buffer register during a first phase of a data write operation started by the reception of a first command. A second data transfer means receives the data provided by the memory bus and modifies, based on the received data, the data stored in the first buffer register during a second phase of the data write operation started by the reception of a second command. The first transfer means execute a second transfer of the modified data stored in the first buffer register into the second buffer register during a third phase of the data write operation. The second transfer is executed in response to the reception of a signal received by the memory bus together with the second command.

What is claimed is: 
     
       1. A non-volatile memory device couplable with a memory bus adapted to provide data to be stored into the memory device and commands to be executed by the memory device, said memory device comprising:
 a memory matrix including memory elements adapted to memorize the data in a non-volatile way; 
 at least a first buffer register configured to receive and memorize in a volatile way the data to be stored into the memory device provided by the memory bus; 
 a command window activatable to operatively interpose itself, for the access to the memory matrix, between said at least one first buffer register and said memory matrix, said command window including at least one second buffer register adapted to store in a volatile way data memorized or to be memorized in a group of memory elements; 
 first data transfer means adapted to execute a first transfer of the data stored in the at least one second buffer register to the at least one first buffer register during a first phase of a writing operation of the data into the memory device started by the reception of a first command; 
 second data transfer means adapted to receive the data provided by the memory bus and modify, according to the received data, the data stored in the at least one first buffer register during a second phase of the writing operation of the data started by the reception of a second command, 
 wherein the first transfer means are adapted to execute a second transfer of the modified data stored in the at least one first buffer register to the at least one second buffer register during a third phase of the writing operation of the data, said second transfer being executed in response to the reception of a signal received by the memory bus together with the second command. 
 
     
     
       2. The memory device of  claim 1 , wherein the memory elements of the memory matrix are arranged according to a plurality of rows and a plurality of columns, and a group of memory elements comprises all the memory elements of a matrix row. 
     
     
       3. The memory device of  claim 2 , wherein said at least one first buffer register is adapted to memorize the data memorizable into a group of memory elements. 
     
     
       4. The memory device of  claim 3 , wherein said second phase of the writing operation comprises at least two phases, during each one of which a respective portion of the data to be stored into the memory device is provided by the memory bus and stored into the at least one register, said signal being provided, at the start of the last of said at least two phases. 
     
     
       5. The memory device of  claim 4 , wherein:
 said at least one first buffer register comprises a first plurality of buffer registers, said first and second transfer means being adapted to select a buffer register of said first plurality during the first and second phase of the writing operation; and 
 said at least one second buffer register comprises a second plurality of buffer registers, said first transfer means being adapted to select a buffer register of said first plurality during the third phase of the writing operation. 
 
     
     
       6. The memory device of  claim 5 , wherein said signal includes a flag bit provided together with the second command that starts the last of said at least two phases. 
     
     
       7. The memory device of  claim 6 , wherein:
 the memory elements of the memory matrix are associated with a first memory space, the memory elements of each row of the matrix being associated with a corresponding subspace of the first memory space addressable by means of a corresponding first row address; 
 the second plurality of buffer registers is associated with a second memory space, each register of the second plurality being associated with a corresponding subspace of the second memory space addressable by means of a corresponding second row address. 
 
     
     
       8. The memory device of  claim 7 , wherein the memory bus is adapted to provide a first row address, the data to be stored into the memory device being to be stored into the memory elements of the matrix row corresponding to the first row address. 
     
     
       9. The memory device of  claim 8 , wherein the data to be stored into the memory device are stored into a corresponding buffer register of the second plurality during the first data writing phase if the second address of said buffer register of the second plurality coincides with the first row address provided by the memory bus. 
     
     
       10. The memory device of  claim 9 , wherein said memory device is adapted to be coupled to a memory bus of the DDR type. 
     
     
       11. The memory device of  claim 9 , wherein said memory device is adapted to be coupled to a memory bus of the DDR2 type. 
     
     
       12. An electronic system comprising:
 at least one non-volatile memory device, the memory device comprising,
 a memory matrix including memory elements adapted to memorize the data in a non-volatile way; 
 at least a first buffer register configured to receive and memorize in a volatile way the data to be stored into the memory device provided by the memory bus; 
 a command window activatable to operatively interpose itself, for the access to the memory matrix, between said at least one first buffer register and said memory matrix, said command window including at least one second buffer register adapted to store in a volatile way data memorized or to be memorized in a group of memory elements; 
 first data transfer means adapted to execute a first transfer of the data stored in the at least one second buffer register to the at least one first buffer register during a first phase of a writing operation of the data into the memory device started by the reception of a first command; 
 second data transfer means adapted to receive the data provided by the memory bus and modify, according to the received data, the data stored in the at least one first buffer register during a second phase of the writing operation of the data started by the reception of a second command, wherein the first transfer means are adapted to execute a second transfer of the modified data stored in the at least one first buffer register to the at least one second buffer register during a third phase of the writing operation of the data, said second transfer being executed in response to the reception of a signal received by the memory bus together with the second command; 
 at least one volatile memory device; and 
 a memory controller coupled with the non-volatile memory device and with the volatile memory device by means of the memory bus, said memory controller being adapted to provide data to be stored or receive data stored in the non-volatile memory device or in the volatile memory device, respectively. 
 
 
     
     
       13. A method of storing data in a non-volatile memory device, the method comprising:
 receiving and storing data in at least one first buffer register; 
 activating a command window interposed between the at least one first buffer register and the non-volatile memory device; 
 receiving a first command; 
 in response to the first command, executing a first transfer of data stored in at least one second buffer register to the at least one first buffer register during a first phase of a writing operation of the data into the non-volatile memory; 
 receiving a second command; and 
 in response to the second command, modifying the data stored in the at least one first buffer register during a second phase of the writing operation. 
 
     
     
       14. The method of  claim 13 , further comprising selecting the at least one first buffer register and the at least one second buffer register to comprise volatile memory devices thereby allowing the data to be written with a granularity of bytes. 
     
     
       15. The method of  claim 13 , further comprising setting a base address of the command window. 
     
     
       16. The method of  claim 15 , wherein the base address corresponds to a particular row address of the non-volatile memory device for which the command window overlaps the non-volatile memory device. 
     
     
       17. The method of  claim 15 , further comprising selecting the base address to overlap different portions of the non-volatile memory device. 
     
     
       18. A method of storing data in a non-volatile memory device, the method comprising:
 receiving and storing data in at least one volatile first buffer register; 
 activating a command window interposed between the at least one first volatile buffer register and the non-volatile memory device; 
 executing a first transfer of data stored in at least one second volatile buffer register located within the command window to the at least one first volatile buffer register during a first phase of a writing operation of the data into the non-volatile memory upon the receiving of a first command; and 
 modifying the data stored in the at least one first volatile buffer register during a second phase of the writing operation upon the receiving of a second command. 
 
     
     
       19. The method of  claim 18 , further comprising transferring the data from the at least one second volatile buffer register to the non-volatile memory device during a subsequent operation. 
     
     
       20. The method of  claim 18 , further comprising executing a second transfer of the modified data stored in the at least one first volatile buffer register to the at least one second volatile buffer register during a third phase of the writing operation of the data in response to receiving a signal.